What would you like to have changed or added to Vampirism

A config option to make vampires capable of going hungry, in addition to the thirst requirement. Lore-wise, it could be a "cursed" mode where your body still needs to eat to stay alive, but cannot replenish lost blood or something.

Does this make the mod experience more balanced?

It does not, but I want to be miserable. It also helps with compat for food mods like spice of life and harder natural healing, which change the food-health dynamic.

Can you provide additional resources (etc. textures or models)

Probably won't be necessary.

I think this would be a nice improvement, maybe one could take it a step further; thirst no longer replaces hunger at all but instead accounts for the extra powers vampires have (flight, regeneration etc), while normal human-like behaviour would still be governed by food, making regular farms still relevant and keeping players from just stocking up on hearts late-game.

Making blood a dedicated resources used for skills would be a fundamental change of the blood system (more towards something like BloodMagic uses afaik). I don't think it would be a bad system, maybe even better, but definitively different. I don't think I want such a change at the moment

That's fair, I have been thinking about how blood magic could be incorporated into the mod to effectively transform the progression into something more expansive and engaging in gameplay; elements of it already exist in the form of blood spikes and rituals.
But understandably there is only so much one can do and such a large change can shake things up for the worse if one is not careful!

Spice of life still works, allowing you to eat food to balance your diet and gain the diet bonuses even as a vampire! So that makes vampires not need food for sustenance and for vitamins instead, and I feel like that is good enough :D I am by no means against your idea, just putting my opinion out there